The investigations were carried out on experimental plots in the Zamość region, during 2001-2003. They involved winter wheat genotypes: Alba, Arina, Astron, Juma, Mobela, Sakwa, Tercja, Zorza and SZO – 195. During the flowering phase, 80 heads of each cultivar and the line were inoculated with conidial suspension of F. avenaceum KF 203. In the laboratory, kernels were detached and the number of kernels in 40 heads (4 x 10), kernels yield, and 1000 kernels weight were calculated. Kernels yield reduction compared to the control, resulting from artificial infection of winter wheat heads with F. avenaceum, oscillated from 26% (Astron) to 39% (SZO – 195). However, reduction of TKW was from 6% (Alba) to18% (SZO – 195), and the reduction of kernels number per head from 18.2% (Tercja) to 27.7% (Mobela). The cultivar Astron, in the case of which the mean kernels yield reduction after 3 years of investigations amounted to 26%, was recognized as the least susceptible to infection with F. avenaceum. The most susceptible genotypes were line SZO – 195 and cultivars Mobela and Juma, in the case of which kernels yield reduction amounted to 39% and 35% and 33%, respectively.